(a) Field of the Invention
Broadly speaking, this invention relates to simulated target-training. More particularly, in a preferred embodiment, this invention relates to methods and apparatus for manufacturing motion pictures for use in projection apparatus used in a target practice simulator.
(b) Discussion of the Prior Art
As is well known, the aquisition and maintenance of a high level of skill and markmanship in the use of small arms, such as rifles and pistols, requires frequent practice on the firing range. Recently, it has been found more efficient, and considerably less expensive, to conduct such target practice on a simulated firing range. In one known system, for example, the system disclosed in U.S. Pat. No. 3,888,022 which issued on June 10th, 1975 to H. Pardes et al. and which is assigned to the United States of America as represented by the Secretary of the Army, a motion picture of a target-bearing scene is projected onto a screen. The subject aims at the target with a simulated weapon and fires; however, instead of a bullet, the simulated weapon "shoots" a laser beam at the target. The laser beam is reflected off the screen, back into the projector's optics, where it is imaged onto the lower half of the film, being projected. This film has priorly been prepared such that an aperture appears on the lower half of the film, which aperture is advantageously clear, and in exact alignment with the target on the screen. If the subject has aimed his "rifle" accurately, so that the laser beam registers a "hit" on the screen, the reflected beam will pass through the aperture in the film to be detected by some suitable photo-detector. Obviously, as the target moves about on the screen, the aperture in the lower half of the film will move also. Further, as the target advances or retreats on the screen, the aperture will grow larger or smaller in the same proportion.
Heretofore, such special motion pictures were expensive and time-consuming to manufacture. Typically, they were made by photographing the target-bearing scene in a motion picture camera including a mask such that the scene is recorded on only the upper half of the film. After reversal processing, the film is projected onto a screen so that the top half of the screen contains the picture and the bottom half is dark. A white spot of the correct size is then manually positioned on the lower half of the screen, using a pantograph, for example, so that the white spot is located in the same relative position as the target of interest on the upper half of the screen.
The entire screen, including the photographic scene and the image of the aperture mask, is then re-photographed so that, after processing, if the two halves of the film are superimposed, only the target would appear through the aperture in the mask.
This mask positioning operation and the re-photographing of the combined image is repeated, frame by frame, each time positioning the mask spot at the proper location on the screen.
It goes without saying, that the above-described process is slow and tedious; worse than that, it results in a master training film that is of poor photographic quality because it is a second generation image obtained by photographing an image that has been projected on a screen.